Study finds link between healthy diet low in sugar and younger biological age

Researchers at the University of California, San Francisco have found a link between a diet rich in vitamins and minerals, particularly one low in added sugar, and reduced biological age at the cellular level.

The researchers looked at how three different measures of healthy eating affected the “epigenetic clock” — a biochemical test that can estimate both health and longevity — and found that people who ate better had younger looking cells. Even those who ate a healthy diet increased their epigenetic age with every gram of added sugar they consumed.

“The diets we looked at are consistent with existing recommendations for disease prevention and health promotion, particularly emphasizing the benefits of antioxidants and anti-inflammatory nutrients,” said Dorothy Chiu, PhD, a postdoctoral researcher in the UCSF Osher Center for Integrative Health and first author of the study, which will be published July 29. JAMA Network Open“From a lifestyle medicine perspective, it’s powerful to know that by following these recommendations, we may be able to make our cellular age younger relative to our chronological age.”

This study is one of the first to show a link between added sugars and epigenetic aging, and it is also the first to examine this association in a diverse group of midlife black and white women; most research on this topic has focused on older white participants.

The research helps improve our understanding of why sugar is so harmful to our health, added Elissa Epel, PhD, professor in the UCSF Department of Psychiatry and Behavioral Sciences and co-senior author of the study.

“We knew that high levels of added sugars, perhaps more than any other dietary factor, are linked to poor metabolic health and early disease. Now we know that accelerated epigenetic aging underlies this relationship, which may be one of the many ways that excess sugar intake limits healthy lifespan.”

Elissa Epel, PhD, professor in the Department of Psychiatry and Behavioral Sciences at UCSF

The women surveyed reported consuming an average of 61.5 grams of added sugars per day, although the range of intake was wide, from 2.7 to 316 grams per day. One bar of milk chocolate contains about 25 grams of added sugars, and a 12-ounce can of cola contains about 39 grams of added sugars. The U.S. Food and Drug Administration recommends that adults consume no more than 50 grams of added sugars per day.

Nutrition-Based Approach

For the cross-sectional study, the researchers analyzed the food records of 342 black and white women in Northern California with an average age of 39. They then compared their diets with measurements of the epigenetic clock obtained from saliva samples.

The researchers scored the women’s diets to compare them with a Mediterranean diet rich in anti-inflammatory and antioxidant foods, and also to diets associated with a lower risk of chronic disease.

Finally, the team scored the women’s diets against a measure they developed called the Epigenetic Nutrition Index (ENI), which is based on nutrients (not foods) associated with antioxidant and anti-inflammatory properties, and DNA maintenance and repair, including vitamins A, C, B12, E, folate, selenium, magnesium, fiber, and isoflavones.

Adherence to any diet was significantly associated with lower epigenetic age, with the strongest association being with the Mediterranean diet.

 
The researchers looked at sugar intake separately and found that consuming foods with added sugar accelerates biological aging, even in those who eat a healthy diet.

“Because epigenetic patterns appear to be reversible, eliminating 10 grams of added sugars per day, if sustained over the long term, may be equivalent to turning back one’s biological clock by 2.4 months,” said co-senior author Barbara Laraia, PhD, R.D., professor in the Food, Nutrition and Population Health Program at the University of California, Berkeley. “Emphasis on foods rich in key nutrients and low in added sugars may be a new way to motivate people to eat healthier diets to live longer.”